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Leaf decomposition is a key process in stream ecosystems within forested catchments; it is driven by microbial communities, particularly fungi and bacteria. These microorganisms make nutrients and energy bound in leaves available for wider parts of the food web. Leaf‐associated microorganisms are subjected to anthropogenic pressures, such as the increased exposure to nutrients and fungicides associated with land‐use change. We assessed the sensitivity of leaf‐associated microbial communities with differing exposure histories, namely, from pristine (P) streams, and streams impacted by wastewater (W) and agricultural run‐off (vineyards; V). In the laboratory, microbial communities were exposed to elevated nutrient (NO3‐N: 0.2–18.0 mg/L, PO4‐P: 0.02–1.8 mg/L) and fungicide concentrations (sum concentration 0–300 µg/L) in a fully crossed 3 × 4 × 4‐factorial design over 21 days. Leaf decomposition and exoenzyme activity were measured as functional endpoints, and fungal community composition and microbial abundance served as structural variables. Overall, leaf decomposition did not differ between fungicide treatments or exposure histories. Nonetheless, substantial changes in the fungal community composition were observed after exposure to environmentally relevant fungicide concentrations. Elevated nutrient concentrations assisted leaf decomposition, and the effect size depended on the exposure history. The observed changes in the fungal community composition support the principle of functional redundancy, with highly efficient decomposers maintaining leaf decomposition. Environ Toxicol Chem 2024;43:1300–1311. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Global species richness is a key biodiversity metric. Concerns continue to grow over its decline due to overexploitation and habitat destruction by humans. Despite recent efforts to estimate global species richness, the resulting estimates have been highly uncertain and often logically inconsistent. Estimates lower down either the taxonomic or geographic hierarchies are often larger than those above. Further, these estimates have been typically represented in a wide variety of forms, including intervals (a, b), point estimates with no uncertainty, and point estimates with either symmetrical or asymmetrical bounds, making it difficult to combine information across different studies. Here, we develop a Bayesian hierarchical approach to estimate global species richness (we estimate 22.02 m species; 95% highest posterior density (HPD) interval (10.43 million, 35.28 million)) that combines 50 estimates from published studies. The data mix of intervals and point estimates are reconciled using techniques from symbolic data analysis. This approach allows us to recover interval estimates at each species level, even when data are partially or wholly unobserved, while respecting logical constraints, and to determine the effects of estimation on the whole hierarchy of obtaining future estimates for particular taxa at various levels in the hierarchy. [ABSTRACT FROM AUTHOR]

In viviparous ectotherms, the interval between reproductive bouts is often extended by long gestation times, preventing multiple reproductive events per annum., We assessed the potential roles of physiological adaptation and environmental constraints in driving an unusual case of geographic variation in life history, in the viviparous lizard ( Eulamprus quoyii), which has either one or two reproductive bouts per annum, depending on the geographic location of the population., Using dynamic energy budget theory, we developed an integrated model of the energetics of growth and reproduction in this lizard, and applied it in conjunction with biophysical calculations of body temperature and activity time across its geographic range to predict reproductive frequency., Our model indicated that geographic variation in body temperature alone (i.e. environmental constraints) explained the observed pattern of litter frequency, suggesting that differences in energy allocation among populations were unlikely to be a major cause of differences in litter frequency in E. quoyii. It also suggested that natural selection should favour fixation of litter size in the transition zone. [ABSTRACT FROM AUTHOR]

Objective. To compare absorbable gelatin sponge (AGS) with an injectable esterified hyaluronic acid (EHA) as middle ear packing material after mucosal trauma.Study Design. Randomized, blinded, and controlled study.Setting. Tertiary university-based hospital.Subjects and Methods. Twenty-three guinea pigs underwent middle ear surgery with mucosal trauma performed on both ears and one ear packed with either EHA or AGS. Contralateral ears were used as nonpacked paired controls. Auditory brainstem response (ABR) thresholds were measured preoperatively and repeated at 1, 2, and 6 weeks postoperatively. Macroscopic and microscopic analysis measured inflammatory reaction in each group.Results. ABR threshold changes from baseline in the EHA and both control groups were minor. Threshold levels were higher in the AGS group compared with the AGS control group. This trend was seen in each frequency tested at each time interval. Macroscopic analysis showed tympanic membrane perforation was rare, effusions were common in the AGS group, mucosal edema was most frequent in the AGS group, and unabsorbed packing was usually detected in the AGS group with little EHA detectable at 6 weeks. Microscopic analysis showed normal mucosal healing in all groups. Two AGS ears demonstrated excessive middle ear packing with exuberant osteoneogenesis.Conclusions. Middle ear function and mucosal healing after surgery occurred similarly between the EHA control group and the EHA group. In contrast, the AGS group demonstrated worse hearing and a greater level of osteoneogenesis compared with the AGS control group. These results support EHA as an alternative middle ear packing material in otologic surgery. [ABSTRACT FROM PUBLISHER]